It is known to use miniature lamps with or without plug bases for decorating Christmas trees and for other purposes. These require suitable sockets on the electric wire. A process is also known for manufacturing, continuously and automatically, sockets for plug-in microlamps on a flexible two-wire cable as an electric line cord insures feed continuity of the cord throughout the working phases of preparation whereafter injection molding of a socket is effected for each completed cycle. Since the working cycle comprises several phases and while the various mechanical operations take place very quickly, the socket-molding phase involves more time to enable the molded object to cool. This means that the time involved in completing the cycle is conditioned upon the time involved in the socket-molding phase.